The following data show the results from an independent-measures study comparing two treatments. a. Compute the independent-measures t statistic for these data. b. Compute the percentage of variance explained by the treatment effect (r2). b.)Treatment \[\begin{array} { l l } \mathrm { I } & \mathrm { II } \\ 1 & 6 \\ 6 & 13 \\ 6 & 12 \\ 3 & 9 \\ \hline \mathrm { M } = 4 & \mathrm { M } = 10 \\ \mathrm { SS } = 18 & \mathrm { SS } = 30 \end{array}\] c. Convert the data into a form suitable for calculating the point-biserial correlation, and compute the correlation. (You should find that squaring the point-biserial correlation will produce the same r2 value that you obtained in part

a.The pooled variance is 8,the estimated

Exam 15: Correlation

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of a ____.

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Question 1

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Compute the Pearson correlation for the following data. 8 0 6 1 4 4 3 6 4 6 5 1

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Question 2

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SS_X = 16,SS_Y = 36,SP = 21,r = 0.875.

Under what circumstances is the point-biserial correlation used?

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A researcher measures driving distance from college and weekly expense on gas for a group of commuting college students.What kind of correlation is likely to be obtained for these two variables?

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Question 4

The value for a correlation can never be greater than +1.00.

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Question 5

The term correlation refers to a statistical technique that is used to ____.

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Question 6

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 6?Scores: 1,1,3,6,6,6,9

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Question 7

The sum of products (SP)is used to measure the amount of covariability between two variables.

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Question 8

The phi-coefficient is the correct correlation to use when both X and Y are dichotomous variables.

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Question 9

The Pearson correlation measures the degree and the direction of the linear relationship between two variables.

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Question 10

In a test for significance of a Pearson correlation for a sample of n = 30 individuals,one determines the critical value by using df = 29.

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Question 11

A set of n = 15 pairs of scores (X and Y values)has SS_X = 4,SS_Y = 25,and SP = 6.The Pearson correlation for these data is ____.?

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Question 12

For a set of n = 10 pairs of scores with ΣX = 10,ΣY = 40,and ΣXY = 50,the sum of products of deviation is SP = 10.

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Question 13

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 1?Scores: 1,1,1,1,3,6,6,6,9

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Question 14

For which of the following correlations would the data points be clustered most closely around a straight line?

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Question 15

Assuming that other factors are constant,a correlation of r = 0.95 will result in more accurate predictions than a correlation of r = +0.70.

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Question 16

The sign (+ or -)and the strength of a correlation are independent of each other.

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Question 17

The value r² is called the coefficient of determination because it measures the proportion of variability in one variable that can be determined from the relationship with the other variable.

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Question 18

The following data show the results from an independent-measures study comparing two treatments. a. Compute the independent-measures t statistic for these data. b. Compute the percentage of variance explained by the treatment effect (r²). b.)Treatment 1 6 6 13 6 12 3 9 =4 =10 =18 =30 c. Convert the data into a form suitable for calculating the point-biserial correlation, and compute the correlation. (You should find that squaring the point-biserial correlation will produce the same r² value that you obtained in part

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Question 19

The Spearman correlation is used to measure the relationship when both variables have been measured on an ordinal scale (both are ranks).

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Question 20

Showing 1 - 20 of 76

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of a ____.

Compute the Pearson correlation for the following data. 8 0 6 1 4 4 3 6 4 6 5 1

Under what circumstances is the point-biserial correlation used?

A researcher measures driving distance from college and weekly expense on gas for a group of commuting college students.What kind of correlation is likely to be obtained for these two variables?

The value for a correlation can never be greater than +1.00.

The term correlation refers to a statistical technique that is used to ____.

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 6?Scores: 1,1,3,6,6,6,9

The sum of products (SP)is used to measure the amount of covariability between two variables.

The phi-coefficient is the correct correlation to use when both X and Y are dichotomous variables.

The Pearson correlation measures the degree and the direction of the linear relationship between two variables.

In a test for significance of a Pearson correlation for a sample of n = 30 individuals,one determines the critical value by using df = 29.

A set of n = 15 pairs of scores (X and Y values)has SS_X = 4,SS_Y = 25,and SP = 6.The Pearson correlation for these data is ____.?

For a set of n = 10 pairs of scores with ΣX = 10,ΣY = 40,and ΣXY = 50,the sum of products of deviation is SP = 10.

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 1?Scores: 1,1,1,1,3,6,6,6,9

For which of the following correlations would the data points be clustered most closely around a straight line?

Assuming that other factors are constant,a correlation of r = 0.95 will result in more accurate predictions than a correlation of r = +0.70.

The sign (+ or -)and the strength of a correlation are independent of each other.

The value r² is called the coefficient of determination because it measures the proportion of variability in one variable that can be determined from the relationship with the other variable.

The Spearman correlation is used to measure the relationship when both variables have been measured on an ordinal scale (both are ranks).

Introduction to Statistics

Frequency Distributions

Central Tendency

Variability

Z-Scores: Location of Scores and Standardized Distributions

Probability

Probability and Samples: the Distribution of Sample Means

Introduction to Hypothesis Testing

Introduction to the T Statistic

The T Test for Two Independent Samples

The T Test for Two Related Samples

Introduction to Analysis of Variance

Repeated-Measures Analysis of Variance Anova

Two-Factor Analysis of Variance Independent Measures

Introduction to Regression

The Chi-Square Statistic: Tests for Goodness of Fit and Independence

The Binomial Test

Filters

Exam 15: Correlation

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of a ____.​

Compute the Pearson correlation for the following data.​ 8 0 6 1 4 4 3 6 4 6 5 1

Under what circumstances is the point-biserial correlation used?​

A researcher measures driving distance from college and weekly expense on gas for a group of commuting college students.What kind of correlation is likely to be obtained for these two variables?​

The value for a correlation can never be greater than +1.00.

The term correlation refers to a statistical technique that is used to ____.​

​If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 6?Scores: 1,1,3,6,6,6,9

The sum of products (SP)is used to measure the amount of covariability between two variables.

The phi-coefficient is the correct correlation to use when both X and Y are dichotomous variables.

The Pearson correlation measures the degree and the direction of the linear relationship between two variables.

In a test for significance of a Pearson correlation for a sample of n = 30 individuals,one determines the critical value by using df = 29.​

A set of n = 15 pairs of scores (X and Y values)has SSX = 4,SSY = 25,and SP = 6.The Pearson correlation for these data is ____.?

For a set of n = 10 pairs of scores with ΣX = 10,ΣY = 40,and ΣXY = 50,the sum of products of deviation is SP = 10.

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 1?Scores: 1,1,1,1,3,6,6,6,9​

​For which of the following correlations would the data points be clustered most closely around a straight line?

Assuming that other factors are constant,a correlation of r = 0.95 will result in more accurate predictions than a correlation of r = +0.70.​

The sign (+ or -)and the strength of a correlation are independent of each other.

The value r2 is called the coefficient of determination because it measures the proportion of variability in one variable that can be determined from the relationship with the other variable.

The Spearman correlation is used to measure the relationship when both variables have been measured on an ordinal scale (both are ranks).

Introduction to Statistics

Frequency Distributions

Central Tendency

Variability

Z-Scores: Location of Scores and Standardized Distributions

Probability

Probability and Samples: the Distribution of Sample Means

Introduction to Hypothesis Testing

Introduction to the T Statistic

The T Test for Two Independent Samples

The T Test for Two Related Samples

Introduction to Analysis of Variance

Repeated-Measures Analysis of Variance Anova

Two-Factor Analysis of Variance Independent Measures

Introduction to Regression

The Chi-Square Statistic: Tests for Goodness of Fit and Independence

The Binomial Test

Filters

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of a ____.

Compute the Pearson correlation for the following data. 8 0 6 1 4 4 3 6 4 6 5 1

Under what circumstances is the point-biserial correlation used?

A researcher measures driving distance from college and weekly expense on gas for a group of commuting college students.What kind of correlation is likely to be obtained for these two variables?

The term correlation refers to a statistical technique that is used to ____.

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 6?Scores: 1,1,3,6,6,6,9

In a test for significance of a Pearson correlation for a sample of n = 30 individuals,one determines the critical value by using df = 29.

A set of n = 15 pairs of scores (X and Y values)has SS_X = 4,SS_Y = 25,and SP = 6.The Pearson correlation for these data is ____.?

If the following seven scores are ranked from smallest to largest,then what rank should be assigned to a score of X = 1?Scores: 1,1,1,1,3,6,6,6,9

For which of the following correlations would the data points be clustered most closely around a straight line?

Assuming that other factors are constant,a correlation of r = 0.95 will result in more accurate predictions than a correlation of r = +0.70.

The value r² is called the coefficient of determination because it measures the proportion of variability in one variable that can be determined from the relationship with the other variable.